Water Scarcity under Various Socio-economic Pathways and its Potential Effects on Food Production in the Yellow River Basin

Increasing population and socio-economic development have put great pressure on water resources of the Yellow River (YR) basin. The anticipated climate and socio-economic changes may further increase water stress. Many studies have investigated the changes in renewable water resources under various climate change scenarios but few have considered the joint pressure from both climate change and socio-economic development. In this study, we assess water scarcity under various socio-economic pathways with an emphasis on the impact of water scarcity on food production. The water demands in the 21st century are estimated based on the newly developed Shared Socio-economic Pathways (SSPs) and the renewable water supply is obtained from the climate projections under the RCP 8.5 scenario. The assessment predicts that the renewable water resources and domestic water demand are projected to first increase and then decrease, while the industrial water demand is projected to rapidly increase in the basin during the 21st century. The water demands will put the middle and lower reaches in conditions of severe water scarcity beginning in the next a few decades (during 1990s–2040s). The industrial water demand is the main contributing factors to water scarcity. The irrigation water demand is another important contributing factor under SSP3. If more than 10 % of the renewable water resources are used to sustain ecosystems, a portion of irrigated land would have to be converted to rain-fed agriculture which would lead to a 9–38 % reduction in food production. This study highlights the links between water, food and ecosystems in a changing environment and suggests that trade-offs should be considered when developing regional adaptation strategies.